Basic question : How to add new packages in RH ES 4

[Maxim Vexler]

Well...

I'm sorry for this but I have no idea how the package management of
RedHat EL works.

I need to add basic software, such as for example graphical Internet.
I used the system-config-packages utility but it demands for a CD #2,
I currently don't have a cdrom no this system but I do have legal
access to rhn.

How would I install additional software without the original
installation media ? Specifically I would like to add FireFox as a web
browser.

Thank you.

--
Cheers,
Maxim Vexler (hq4ever).

Do u GNU ?